//
// Created by martin on 1/27/22.
//

#include "LogStream.h"

#include <algorithm>

// printf 64bit, use PRId64 for x64/x86
// see https://www.cnblogs.com/mickole/articles/3246042.html
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif

#include <inttypes.h>

using namespace muduo;
using namespace muduo::detail;

// TODO: better itoa.
#if defined(__clang__)
#pragma clang diagnostic ignored "-Wtautological-compare"
#else
#pragma GCC diagnostic ignored "-Wtype-limits"
#endif

namespace muduo
{
namespace detail
{

const char digits[] = "9876543210123456789";
const char* zero = digits + 9; // zero pointer to '0'

static_assert(sizeof(digits) == 20, "wrong number of digits");

const char digitsHex[] = "0123465789ABCDEF";
static_assert(sizeof(digitsHex) == 17, "wrong number of digitsHex");

/* Efficient Integer to String Conversions, by Matthew Wilson. */
template<typename T>
size_t convert(char buf[], T value)
{
    T i = value;
    char* p = buf;

    do {
        int lsd = static_cast<int>(i % 10);
        i /= 10;
        *p++ = zero[lsd];
    } while (i != 0);

    if (value < 0)
    {
        *p++ = '-';
    }
    *p = '\0';
    std::reverse(buf, p);

    return static_cast<size_t>(p - buf);
}

size_t convertHex(char buf[], uintptr_t value)
{
    uintptr_t i = value;
    char* p = buf;

    do
    {
        int lsd = static_cast<int>(i % 16); // last digit for hex number
        i /= 16;
        *p++ = digitsHex[lsd];
    } while (i != 0);

    *p = '\0';
    std::reverse(buf, p);
    return static_cast<size_t>(p - buf);
}

template class FixedBuffer<kSmallBuffer>;
template class FixedBuffer<kLargeBuffer>;

} // namespace detail

/*
 * Format a number with 5 characters, including SI units.
 * [0, 999]
 * [1.00K, 999K]
 * [1.00M, 999M]
 * [1.00G, 999G]
 * [1.00T, 999T]
 * [1.00P, 999P]
 * [1.00E, inf]
 */
string formatSI(int64_t s)
{
    double n = static_cast<double>(s);
    char buf[64];
    if (s < 1000)
        snprintf(buf, sizeof(buf), "%" PRId64, s);
    else if (s < 9995)
        snprintf(buf, sizeof(buf), "%.2fk", n/1e3);
    else if (s < 99950)
        snprintf(buf, sizeof(buf), "%.1fk", n/1e3);
    else if (s < 999500)
        snprintf(buf, sizeof(buf), "%.0fk", n/1e3);
    else if (s < 9995000)
        snprintf(buf, sizeof(buf), "%.2fM", n/1e6);
    else if (s < 99950000)
        snprintf(buf, sizeof(buf), "%.1fM", n/1e6);
    else if (s < 999500000)
        snprintf(buf, sizeof(buf), "%.0fM", n/1e6);
    else if (s < 9995000000)
        snprintf(buf, sizeof(buf), "%.2fG", n/1e9);
    else if (s < 99950000000)
        snprintf(buf, sizeof(buf), "%.1fG", n/1e9);
    else if (s < 999500000000)
        snprintf(buf, sizeof(buf), "%.0fG", n/1e9);
    else if (s < 9995000000000)
        snprintf(buf, sizeof(buf), "%.2fT", n/1e12);
    else if (s < 99950000000000)
        snprintf(buf, sizeof(buf), "%.1fT", n/1e12);
    else if (s < 999500000000000)
        snprintf(buf, sizeof(buf), "%.0fT", n/1e12);
    else if (s < 9995000000000000)
        snprintf(buf, sizeof(buf), "%.2fP", n/1e15);
    else if (s < 99950000000000000)
        snprintf(buf, sizeof(buf), "%.1fP", n/1e15);
    else if (s < 999500000000000000)
        snprintf(buf, sizeof(buf), "%.0fP", n/1e15);
    else
        snprintf(buf, sizeof(buf), "%.2fE", n/1e18);
    return buf;
}

/*
 [0, 1023]
 [1.00Ki, 9.99Ki]
 [10.0Ki, 99.9Ki]
 [ 100Ki, 1023Ki]
 [1.00Mi, 9.99Mi]
*/
std::string formatIEC(int64_t s)
{
    double n = static_cast<double>(s);
    char buf[64];
    const double Ki = 1024.0;
    const double Mi = Ki * 1024.0;
    const double Gi = Mi * 1024.0;
    const double Ti = Gi * 1024.0;
    const double Pi = Ti * 1024.0;
    const double Ei = Pi * 1024.0;

    if (n < Ki)
        snprintf(buf, sizeof buf, "%" PRId64, s);
    else if (n < Ki*9.995)
        snprintf(buf, sizeof buf, "%.2fKi", n / Ki);
    else if (n < Ki*99.95)
        snprintf(buf, sizeof buf, "%.1fKi", n / Ki);
    else if (n < Ki*1023.5)
        snprintf(buf, sizeof buf, "%.0fKi", n / Ki);

    else if (n < Mi*9.995)
        snprintf(buf, sizeof buf, "%.2fMi", n / Mi);
    else if (n < Mi*99.95)
        snprintf(buf, sizeof buf, "%.1fMi", n / Mi);
    else if (n < Mi*1023.5)
        snprintf(buf, sizeof buf, "%.0fMi", n / Mi);

    else if (n < Gi*9.995)
        snprintf(buf, sizeof buf, "%.2fGi", n / Gi);
    else if (n < Gi*99.95)
        snprintf(buf, sizeof buf, "%.1fGi", n / Gi);
    else if (n < Gi*1023.5)
        snprintf(buf, sizeof buf, "%.0fGi", n / Gi);

    else if (n < Ti*9.995)
        snprintf(buf, sizeof buf, "%.2fTi", n / Ti);
    else if (n < Ti*99.95)
        snprintf(buf, sizeof buf, "%.1fTi", n / Ti);
    else if (n < Ti*1023.5)
        snprintf(buf, sizeof buf, "%.0fTi", n / Ti);

    else if (n < Pi*9.995)
        snprintf(buf, sizeof buf, "%.2fPi", n / Pi);
    else if (n < Pi*99.95)
        snprintf(buf, sizeof buf, "%.1fPi", n / Pi);
    else if (n < Pi*1023.5)
        snprintf(buf, sizeof buf, "%.0fPi", n / Pi);

    else if (n < Ei*9.995)
        snprintf(buf, sizeof buf, "%.2fEi", n / Ei );
    else
        snprintf(buf, sizeof buf, "%.1fEi", n / Ei );
    return buf;
}

} // namespace muduo

LogStream& LogStream::operator<<(short v) {
    *this << static_cast<int>(v);
    return *this;
}

LogStream& LogStream::operator<<(unsigned short v) {
    *this << static_cast<int>(v);
    return *this;
}

LogStream& LogStream::operator<<(int v) {
    formatInteger(v);
    return *this;
}

LogStream& LogStream::operator<<(unsigned int v) {
    formatInteger(v);
    return *this;
}

LogStream& LogStream::operator<<(long v) {
    formatInteger(v);
    return *this;
}

LogStream& LogStream::operator<<(unsigned long v) {
    formatInteger(v);
    return *this;
}

LogStream& LogStream::operator<<(long long v) {
    formatInteger(v);
    return *this;
}

LogStream& LogStream::operator<<(unsigned long long v) {
    formatInteger(v);
    return *this;
}

LogStream::self &LogStream::operator<<(const void* p)
{
    uintptr_t v = reinterpret_cast<uintptr_t>(p);
    if (buffer_.avail() >= kMaxNumericSize)
    {
        char* buf = buffer_.current();
        buf[0] = '0';
        buf[1] = 'x';
        size_t len = convertHex(&buf[2], v);
        buffer_.add(len + 2);
    }
    return *this;
}

template<typename T>
void LogStream::formatInteger(T v)
{
    if (buffer_.avail() >= kMaxNumericSize)
    {
        size_t len = convert(buffer_.current(), v);
        buffer_.add(len);
    }
}

template<int SIZE>
const char *FixedBuffer<SIZE>::debugString()
{
    *cur_ = '\0';
    return data_;
}

template<int SIZE>
void FixedBuffer<SIZE>::cookieStart()
{
}

template<int SIZE>
void FixedBuffer<SIZE>::cookieEnd()
{
}

void LogStream::staticCheck()
{
    static_assert(kMaxNumericSize - 10 > std::numeric_limits<double>::digits10,
            "kMaxNumericSize is large enough");
    static_assert(kMaxNumericSize - 10 > std::numeric_limits<long double>::digits10,
            "kMaxNumericSize is large enough");
    static_assert(kMaxNumericSize - 10 > std::numeric_limits<long>::digits10,
            "kMaxNumericSize is large enough");
    static_assert(kMaxNumericSize - 10 > std::numeric_limits<long long>::digits10,
            "kMaxNumericSize is large enough");
}

LogStream::self &LogStream::operator<<(double v)
{
    if (buffer_.avail() >= kMaxNumericSize)
    {
        int len = snprintf(buffer_.current(), kMaxNumericSize, "%.12g", v );
        buffer_.add(static_cast<size_t>(len));
    }
    return *this;
}
